\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*} WF^{(3.3+((-log_{10}(10-WF)+1) \times (-log_{10}(10-WF)/2) \times 0.2))} \end{equation*}
\end{document}
